In this section, we provide answers to some of the more common questions we receive about our 3D vision technology, stereo imaging and the range of application for these techniques.

A Comparison of 3D Technologies

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  • Relatively low cost – ranging from a few £100s. Even industrial units cost less than an entry-level LIDAR scanner
  • Highly customisable (lens choices, filters, baselines, ruggedisation, etc)
  • Obtain both 2D and 3D data. 2D information may be more beneficial for image analysis (e.g. defect detection) and machine learning.
  • Can overlay image intensity/colour directly on 3D
  • Output is a point cloud
  • Highest resolution of any 3D imaging solution (megapixels)
  • High data rates (stereo may be produced at 60fps for low-resolution images). Images may be acquired in a few ms.
  • Suitable for imaging moving targets
  • Power consumption is low (can be powered from USB alone)
  • Mechanically robust – no moving parts
  • Accuracy is very good (sub-mm for Phobos)
  • Works indoors and outdoors
  • May use different algorithms depending on scene/task
  • Calibration is straightforward and may be done by the end-user
  • Stereo camera systems which make 1 million + measurements per observation are inherently resistant to high temperature and humidity levels therefore can provide information regardless of ambient air temperatures. This makes stereo more practical and more deployable.


  • Reconstruction relies on there being lots of features in the scene
  • Accuracy is quadratically dependent on the range (e.g. double distance, accuracy down by a factor of four)
  • Passive sensing so may need illumination (especially if dark/ featureless surface)
  • High-resolution algorithms will need high-performance GPUs.
  • Potentially needs expert oversight to advise on the best setup for a particular scene (lots of parameters)
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  • Easy to set up
  • Very robust imaging – can reconstruct virtually any opaque surface
  • Output is a point cloud
  • Good accuracy over full measurement range (mm to cm)
  • Can measure up to hundreds of metres
  • High resolution – scans can be arbitrarily dense at the expense of scanning time; pretty fast – 1M point per second typical now
  • Works indoors and outdoors
  • Calibration usually not required by the user


  • Intensity information (colour) must be overlaid using a separate, calibrated, camera
  • System must be scanned
  • Somewhat mechanically robust, but contains precision moving parts (not good for many industrial environments
  • Not suitable for extended use in harsh environments (though many systems are weatherproof/IP rated for outdoor use)
  • Not suitable for moving targets
  • Scans tend to be sparse, or can spend more time to ‘fill in the gaps’
  • Expensive, systems start at £20k
  • Needs a lot of power
  • Heavy and bulky (although newer automotive LIDAR will change this)
  • Is susceptible to ‘heat haze’ when the air temperature exceeds 23 C, particularly, if there is a high level of humidity when the air can become turbulent. In extreme cases, the heat can make laser light scintillate destroying any information.
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Time-of-flight Cameras

e.g. Kinect v2 (“Kinect for Xbox One”), SwissRanger


  • Can be very low cost (< £100) but comparable to stereo systems for industrial units
  • Reasonably high resolution (1MP)
  • Fast frame rates (30 fps)
  • Images an area, just like a camera
  • Works very well indoors – fine on featureless objects
  • Output is a point cloud


  • Calibration performed by the manufacturer
  • Illumination is power hungry so units require wall power
  • Quite heavy, mostly due to cooling/heatsinks
  • Doesn’t work outside because of NIR illumination
  • Only usable to around 10 m
  • Requires NIR reflective surfaces
  • Can get inaccurate ranges depending on object colour, system temperature, etc. calibration of this is not trivial
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